S100B and Stroke: Multiple studies have observed early elevated plasma levels of S100B in AIS patients who later develop BBB disruption37, 38, however S100B has only exhibited modest levels of diagnostic robustness; in the largest clinical study performed to date evaluating the ability of S100B to identify patients at risk for post-stroke BBB disruption, S100B was only able to do so with 93% sensitivity and 48% specificity38.